Keeping your car’s traction on a slippery surface can be a challenge, whether it’s because of rain or snow, or dirt and gravel. Lost traction represents a real safety threat to drivers and their passengers. This is where all-wheel drive (AWD) and four-wheel-drive (4WD) can help.
These systems are similar in that they both send power to all four wheels. By distributing the vehicle’s power, they help its tires achieve and maintain better traction during acceleration.
Though AWD and 4WD are similar, how they work is different and each system has its own pros and cons.
How Does AWD Work?
In an AWD system, torque is sent to all four of a vehicle’s wheels automatically. Drivers typically don’t need to act to start the process, though some systems offer selectable modes that allow drivers to determine how power is distributed.
There are two types of AWD: full-time and part-time. With a full-time system, torque is sent to all four wheels 24/7. With part-time AWD, power is typically sent to either the front or rear axle during normal driving. Sensors determine if there is a need for extra traction, such as when there’s rain, snow or mud on the ground. Then, the part-time AWD sends power to both axles.
There’s one important note to consider: AWD (and 4WD) only help you with acceleration. They can help you get started on slick surfaces, but neither one is able to brake better than a vehicle with just two-wheel drive, even on a slick surface. They also don’t increase the grip of your tires themselves, so they won’t help you if you’re coasting around a corner, although they can help you maintain traction when you’re accelerating around a corner.
Pros of AWD
- Better Traction When Accelerating on Slippery Surfaces: Drivers who travel frequently in rain or snow will see some serious benefits from AWD. It gives you better control of the vehicle in treacherous situations and can help prevent accidents.
- Better Performance in Sports Cars: Also, some sports cars use AWD systems to boost performance. The added traction that this system provides while accelerating can result in faster launches and cornering.
- Easier to Use Than 4WD: AWD is user-friendly, since it typically requires no input from drivers.
Cons of AWD
- Worse Fuel Economy Than FWD and RWD: Because they have more parts in their drivetrains and weigh more, AWD vehicles deliver poorer mileage than their two-wheel-drive (2WD) counterparts, and this can increase your fuel costs over the long term.
- Not as Effective Off Road as 4WD: When compared to 4WD, AWD isn’t as effective in off-road situations. The typical 4WD system is more rugged than AWD, and this allows it to perform more capably when taken off the beaten path.
- More Expensive Than FWD and RWD: Adding an AWD system can cost thousands of dollars, since it’s typically offered as a relatively expensive option.
What Types of Vehicles Have AWD?
You’ll find AWD offered across a wide range of vehicles. It’s available in hatchbacks such as the Toyota Prius and sedans such as the Ford Fusion. This feature is offered in coupes such as the Porsche 911, wagons such as the Volvo V90, and crossovers such as the Toyota Highlander. You’ll also find AWD in minivans such as the Toyota Sienna and full-size vans such as the Ford Transit.
How Does 4WD Work?
Like AWD, 4WD sends power to all four of a vehicle’s wheels. However, 4WD tends to be more robust than AWD, and this makes that system a better fit for drivers who go off-road. Also, unlike AWD, 4WD typically offers driver-selectable low- and high-range settings. The low-range setting delivers aggressive traction and is usually used when ascending steep trails or crawling over boulders.
With 4WD, both full-time and part-time systems are offered, as is the case with AWD. A full-time 4WD system continuously sends power to all four wheels, although some of these systems allow the driver to choose how power is distributed between the axles. With a part-time system, the default setting sends power to two wheels, and it’s up to the driver to engage 4WD when extra grip is needed. Depending on the vehicle, this may be done by using a switch, lever, or button.
Pros of 4WD
- Does Better Off Road Than AWD: The primary benefit of 4WD is its ability to perform well in off-road situations. This setup is durable and rugged, and it’s a great choice for conquering trails.
- Usually Has an Off Switch: Also, unlike AWD, drivers can sometimes manually deactivate 4WD, allowing the system to deliver better fuel efficiency.
Cons of 4WD
- Worse Fuel Economy: 4WD systems typically achieve poorer mileage than drivers would get with comparable 2WD vehicles. 4WD vehicles usually also achieve worse fuel economy than AWD vehicles, due to the heavier-duty parts they have.
- More Expensive: Like AWD, 4WD is usually offered as a fairly pricey option.
What Types of Vehicles Have 4WD?
You’ll find 4WD in sturdy vehicles built to shine off-road. It’s available in compact trucks such as the GMC Canyon and Toyota Tacoma, as well as full-size trucks such as the Ford F-150 and Chevrolet Silverado. This feature is also offered in off-road-oriented SUVs, such as the Jeep Wrangler and Toyota 4Runner. Last but not least, 4WD is available in full-size SUVs such as the Land Rover Range Rover and Chevrolet Tahoe.
AWD vs 4WD: Which Should I Choose?
It comes down to one real question: Are you going to take your vehicle off-roading?
For the small percentage of people who spend a great deal of time off-road, 4WD makes the most sense. This system is tough enough to tackle the great outdoors.
However, we imagine most drivers are primarily interested in a system that can hold its own in rainy and snowy conditions. If you’re mainly concerned with boosting traction on wet or icy roads, AWD gets the job done, and it’s available in a wider variety of vehicles, many of which offer a more comfortable ride than their 4WD counterparts.
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